Question: $f(n) = -2n$ $h(n) = -7n^{2}-6n-4(f(n))$ $g(n) = -n-5(f(n))$ $ f(g(5)) = {?} $
Solution: First, let's solve for the value of the inner function, $g(5)$ . Then we'll know what to plug into the outer function. $g(5) = -5-5(f(5))$ To solve for the value of $g$ , we need to solve for the value of $f(5)$ $f(5) = (-2)(5)$ $f(5) = -10$ That means $g(5) = -5+(-5)(-10)$ $g(5) = 45$ Now we know that $g(5) = 45$ . Let's solve for $f(g(5))$ , which is $f(45)$ $f(45) = (-2)(45)$ $f(45) = -90$